What is analysed?
Haemoglobin is a complex protein found in red blood cells that carries oxygen from the lungs to the tissues and carbon dioxide from the tissues back to the lungs for exhalation.
A haemoglobin analysis measures the level of haemoglobin in the blood. Haemoglobin serves as a marker for the blood’s oxygen-carrying capacity.
What does the result mean?
The result of the test indicates the concentration of haemoglobin in the blood.
Why conduct the analysis?
A haemoglobin analysis is conducted to evaluate the severity and the effectiveness of treatment, of anaemia or polycythaemia.
When to conduct the analysis?
A haemoglobin analysis is conducted as part of a full blood count, a test that provides information about the types and numbers of cells in the blood including red blood cells, platelets, and white blood cells.
What sample is required?
A blood sample is required. The blood is drawn from a vein usually in the arm.
Is any prior preparation necessary?
Patients should drink plenty of fluids before the blood sample is collected.
How is it performed?
The sample is sent to a laboratory, where it is analysed using automated haematology analysers, which measure haemoglobin levels in the blood sample through a process known as spectrophotometry.
What are the normal values?
Below shows typical haemoglobin levels for adults:
- Men: 13.8 to 17.2 g/dL.
- Women: 12.1 to 15.1 g/dL (varies by trimester during pregnancy).
What does having altered values mean?
- High haemoglobin levels: Indicates a condition called polycythaemia (too many red blood cells), which can lead to heart failure and stroke.
- Low haemoglobin levels: Indicates a condition called anaemia (too few red blood cells), in which the body isn’t getting enough oxygen. This can cause symptoms like fatigue and weakness.